It's been a while since I visited Oz; are they likely to check laptops at the airport on arrival, and get upset/arresty for things like porn having been viewed?
The law seems pretty open to interpretation over what is 'objectionable', or 'imported'...but if computer has accidentally downloaded the occasional scene or kept photos in the 'viewed' folder somewhere (all standard stuff, nothing that would be borderline illegal to watch in most developed places)...whats the view?
